Hot weather, Iro not conpensating

I was under the impression that of the main features of the Iro is that would automatically adjust for changing weather conditions. However, I’m not seeing that on my setup going into some hot Las Vegas weather. There is no difference in watering when it’s 80F out verses 105F. It’s predicting 115F for next week and I’m worried some of my plants will not survive the current watering schedule it’s using. I have a weather station (the airport less than a mile away) properly selected from the best I can tell. Did I just misunderatnd the capabilities of the Iro, or is something not functioning correctly. I know I can do some IFTT scripts to add water on hot days, but I thought I was getting that baked in with the product. Thanks!

Are you,on a fixed or flex schedule. Only flex daily is highly reactive.

I took a look and I was setup for Monthly Flex, I changed it to Daily Flex and will keep an eye on how it performs. Is Daily Flex a new thing? I could of sworn when I set this up a month ago that wasn’t an option. Even in Daily Flex it’s currently scheduling almost the exact same interval and length of Monthly Flex. I assume that it will make adjustments on-the-fly and that the schedule days in advance means little in all reality?


Last year “Flexible Daily” was just called “Flex”. It went away for a little bit this year for new users when “Water As Needed” was added, but so many people loved it that the good guys at Rachio brought it back into the fold. “Water As Needed” was renamed to “Flexible Monthly”.

Yes, it will make adjustments on the fly, and while you have a rough idea of what is likely to happen in the future, just like the weather forecast, it will get closer to reality the closer in you get to the event. And it will be pretty darn good on the day that it waters, based on the forecast it has at that time.

Are your zones setup correctly? I’m assuming so since you are not surprised by your watering times.

Yes, it computes et daily, if you go into your zone,settings, you can now see a moisture graph that they track.

@beaker353, I just noticed that you said plants and not lawn. If this is lawn and it’s set up right on Flexible Daily my guess is that you will be OK. But if it’s non-lawn plants, you might want to take a look at the Dante’s Garden thread.

And lucky you to have an airport weather station less than a mile away!

@Linn It’s trees and shrubs. Not the ideal choice for when we get in into the 100teens, but it’s what the original builder put in years ago. Trying to keep a lawn healthy here in the summer here is usually a big pain and can get quite expensive quickly.

As it seems that accurately profiling sounds pretty critical to flex daily, what do people usually do when a zone is a mix of vegetation like mine? The settings for shrubs is 15" root depth and 50% crop coefficient, trees are at 25" root depth and 75% crop coefficient. To be on the safe side I right now I have it set to 15" root depth, and 75% crop coefficient. The watering intervals and lengths look decent for 100F’ish weather, hopefully it will make adjustments when things get into the 110’s.


@azdavidr, would you be able to help @beaker353 out a bit here? Your climates sound similar.

I’m dealing more with mixing annuals and perennials (and a few shrubs) in the same zone. What I did was to kind of average things out – like setting my root depth to either 5 or 6" (still playing with that), and I go with the higher Crop coefficient.

I’m currently handling mine by also adding water using the more/less option as it doesn’t play into the moisture levels. When @azdavidr gets into problems as it gets really nasty, he is running an additional fixed schedule to supplement it (when the ET gets higher than the water the system is putting down).

What we are finding is that when all these things are mixed up in the same zone you have to monitor and play with it a bit to dial it in.

Sure @Linn. @beaker353, are you fairly confident of your soil setting? That’s an important starting point. We have Sandy Loam here. I’m currently watering my shrubs every 5 or 6 days (my crop coefficient is 0.52.) and am giving each shrub 8 gallons (1GPH emitters, 1 per shrub, 8 hour runs). That’s the recommended watering duration for a 3ft canopy shrub here in Phoenix, and also the recommended interval for this time if year.

We got up to 118F here last Sunday and are due to hit 122F in Phoenix tomorrow. With these temps I’ve been checking my shrubs and garden daily. At day 6 one of my many shrubs was showing signs of distress, but the others seem just fine. That was at a crop coefficient of 0.5, so I bumped it up to 0.52 to water at 5 days instead of 6. 75% sounds quite high to me, so I’m guessing you expect more frequent watering?

Screen shots of your zone and schedule would be helpful. Also share your nozzle precipitation rate and your moisture graph with details shown. We should be able to help. There are at least four of us on these boards that are active and can try to point you in the right direction.

1 Like